A. Field of the Invention
This invention relates to a novel crimped bicomponent filament prepared by conjugately melt spinning in a side-by-side relation polyester component, one of which contains CaF.sub.2 uniformly dispersed therein.
B. Description of the Prior Art
It is known that crimped filaments are obtained by conjugately melt spinning in a side-by-side relation two different polymers having different shrinkage properties or two chemically identical polymers having different thermal histories and, thus, different shrinkage properties. The structural heterogeneity (i.e. difference in shrinkage) in the cross-section of these filaments creates internal stresses which produce helical crimp when they are relieved. Filaments having internal stresses which when relieved produce crimp are said to have latent crimp. There are certain drawbacks involved in producing these prior art filaments, for example, one of the filaments requires the spinning of two chemically different polymers while the other filament requires subjecting each polymer to different thermal treatments just prior to melt spinning.